Supplement of Atmos. Chem. Phys., 18, 13197–13214, 2018 https://doi.org/10.5194/acp-18-13197-2018-supplement © Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License.

Supplement of Molecular insights on aging and aqueous-phase processing from ambient biomass burning emissions-influenced Po Valley fog and aerosol

Matthew Brege et al.

Correspondence to: Lynn R. Mazzoleni ([email protected])

The copyright of individual parts of the supplement might differ from the CC BY 4.0 License.

Table of Contents 1. FT-ICR MS data processing and molecular formula assignment review 2. Ultrahigh resolution FT-ICR MS results 3. FT-ICR MS data set 4. Supplemental figures and tables a. Figure S1: Distribution of the molecular formulas by elemental group subclasses b. Figure S2: van Krevelen diagrams of all assigned molecular formulas scaled to number of oxygen atoms c. Figure S3: Reconstructed difference mass spectra of assigned molecular formulas d. Figure S4: Oxygen difference of abundance trends e. Figure S5: Double bond equivalent difference of abundance trends f. Figure S6: Kendrick mass defect diagrams of assigned molecular formulas scaled to number of oxygen atoms for unique molecular formulas per sample g. Figure S7: Kendrick mass defect diagrams of all assigned molecular formulas scaled to number of oxygen atoms h. Table S1: Summary of possible identified molecular formulas

1. FT-ICR MS data processing and molecular formula assignment review

The individual transient scans of FT-ICR MS data for each sample were reviewed manually and the unacceptable scans with an abrupt change in the total ion current were removed; the remaining transient scans were co-added together to create the working file for each sample (this helped to increase signal to noise and enhance sensitivity). Molecular formula assignments were made as previously described (Mazzoleni et al., 2010; Putman et al., 2012; Zhao et al., 2013; Dzepina et al., 2015) using Sierra Analytics Composer software (version 1.0.5) within the limits of: C2-200H4-1000O1-20N0-3S0-1. Masses were calculated from measured m/z values, assuming an ion charge of -1 from the electrospray. The calculator uses a CH2 Kendrick mass defect (KMD) analysis to sort homologous ion series and extend the molecular formula assignments to higher masses (Hughey et al., 2001; Kujawinski and Behn, 2006). A de novo cut-off at m/z 500 was applied, indicating that no new formula assignments would occur above m/z 500, unless the formula was part of an existing CH2 homologous series that began at a point lower than m/z 500. This is necessary because the number of possible molecular formulas increases at higher values. The minimum relative abundance required for molecular formula assignment was > 10 times the estimated signal-to-noise ratio, determined for each sample between m/z 900–1000. Only integer values up to 40 were allowed for the double bond equivalents (DBE). The data set was manually reviewed to remove: formulas with an absolute error > 3 ppm, elemental ratios that were not chemically sensible (such as O:C > 3 or H:C < 0.3), and formulas which violated the rule of 13 or violated the nitrogen rule. The rule of 13 checks for a reasonable number of heteroatoms in a formula. A base formula (CnHn+r) 푀 푟 can be generated for any measured mass by solving: = 푛 + (Pavia, 2009). Then, the maximum number of "large 13 13 atoms" (C, O, N, S) in a formula is defined as the mass divided by 13, because substituting for a heteroatom (O, N or S) involves a substitution for at least one carbon. This maximum number is then compared to the actual number of "large atoms" in a formula, and those formulas exceeding the maximum number are rejected. The nitrogen rule removes formulas with odd masses that do not contain an odd number of nitrogen atoms, and even masses that do not contain an even number (or no) nitrogen atoms; this is due to the odd numbered valence of nitrogen (Pavia, 2009). Molecular formulas that contained 13C or 34S were also removed from the data set. Homologous series with large gaps in the DBE trend were removed, as well as homologous series with a length of one. The assigned formulas were also analyzed with consideration to the DBE and oxygen number trends, (Herzsprung et al., 2014) where unreliable formula assignments were also removed.

2. Ultrahigh resolution FT-ICR MS results

The total ion abundance of the identified monoisotopic molecular formulas reported for each sample was determined by their summation. Then, these values were used to normalize the individual ion abundances within each sample using a ratio of the individual ion intensity to this total ion abundance. Then, the values were rescaled using a normalization constant (10,000). This normalization procedure was done to remove analytical biases introduced by trace contaminants with high electrospray efficiency. Reconstructed difference mass spectra of the assigned molecular formulas for both fog and aerosol samples are shown in Fig. S3. These difference mass spectra permit a direct comparison of the samples using normalized

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relative abundances. The individual relative abundances were normalized by the total abundance of the assigned molecular formulas identified in each of the samples. In Fig. S3, the individual masses with higher abundances in either the positive or negative direction were substantially greater in one of the two samples, whereas the masses of similar abundance tended to cancel each other. To enhance the interpretation of the compositional differences, the individual masses were color-coded to represent the number of oxygen atoms in the assigned formula. Overall, we observed higher numbers of oxygen in the masses of the two samples with aged biomass burning emissions influence compared to the two samples with fresh biomass burning emissions influence. The molecular formulas assigned to the fresh samples had approximately 0-5 oxygen atoms over the mass range of 50-250 Da, 5-10 oxygen atoms over 250- 550 Da, and a few molecular formulas were assigned with 10-15 oxygen atoms over 500-600 Da. In contrast, the aged samples had a large number of molecular formulas with 10-15 oxygen atoms in the range of 400-550 Da. This clearly shows a greater amount of oxidation in the aged influenced samples compared to the fresh influenced samples. KMD diagrams can be used as useful tools to visualize the relationships between the many molecular formulas of complex mixtures such as atmospheric samples. We used Kendrick mass defect to sort the molecular formulas into CH2 homologous series of identical heteroatom content and DBE, where the formulas in the same series differ only by a number of CH2 units (Stenson et al., 2003). It should be noted that the presence of multiple formulas in the same homologous series does not necessarily imply a related chemical structure. The homologous series are visible as horizontal rows of formulas in Figs. S6 and S7. There were multiple homologous series per subclass, where the base formula for each series differ in DBE and increase in KMD to form an ensemble of “steps” within each subclass. In our samples individual CHO and CHNO subclasses had approximately 5-16 different homologous series, while CHOS and CHNOS subclasses had approximately 3-10 different homologous series. The number of homologous series in a subclass increased with oxygen number, and peaked near the median oxygen number, then decreased again towards the maximum number of oxygen; this led to fewer molecular formulas in subclasses with higher and lower oxygen numbers, and more formulas in subclasses near the median oxygen number. The subclasses with the highest numbers of molecular formulas per elemental group were: O7, NO8, O7S and NO9S. It was atypical for the unique formulas of a sample to be completely unrelated to other formulas across the data set; often the unique formulas were extensions of homologous series that appeared across samples.

3. FT-ICR MS data set

An abbreviated list of the complete FT-ICR MS dataset is provided and is available on Digital Commons: http://digitalcommons.mtu.edu/chemistry-fp/98/

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4. Supplemental Figures and tables

Figure S1: Distributions of the molecular formulas within all 64 elemental group subclasses for CHO, CHNO, CHOS and CHNOS groups as indicated in the Figure. The total number of molecular formulas for each SPE-recovered WSOC sample were split into two groups of unique and non-unique formulas; the darker shade represents formulas unique to a sample, (denoted in the Figure legend with an asterisk after the sample name, e.g. “Fresh Fog*”) while the lighter shade represents common formulas. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S2: van Krevelen diagrams for the SPE-recovered WSOC by elemental group (rows) and sample (columns) as indicated in the Figure. Dashed lines represent H:C = 1.2 (horizontal), O:C = 0.6 (vertical) and OSC = 0 (diagonal) as described in Tu et al. (2016). Formulas are color scaled to the number of oxygen atoms in the assigned formula. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S3: Reconstructed difference mass spectra for theoretical masses of assigned molecular formulas in the Po Valley samples with normalized relative abundance. Fresh influenced samples (SPC0106F and BO0204N) are plotted with positive abundance and aged influenced samples (SPC0201F and BO0213D) are plotted with negative abundance. Molecular compositions in both samples with the same mass and similar normalized relative abundance are reduced toward zero. The peaks in the mass spectra are color scaled to the number of oxygen atoms in the assigned molecular formula, where it can be observed that the aged samples shift towards species with higher oxygen numbers at lower masses, compared to the fresh samples. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S4: Oxygen difference trends for aerosol (a) and fog (b) samples. Abundance trends were calculated as in Figure 6 of the main text, and then the respective aged sample normalized abundance was subtracted from the fresh sample normalized abundance for each oxygen number value. A positive difference of abundance indicates an enhanced abundance of formulas in the fresh sample compared to the aged sample. Similarly, a negative difference of abundance indicates an enhanced abundance of formulas in the aged sample compared to the fresh sample. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S5: Double bond equivalent difference trends for aerosol (a) and fog (b) samples. Abundance trends were calculated as in Figure 6 of the main text, and then the respective aged sample normalized abundance was subtracted from the fresh sample normalized abundance for each integer double bond equivalent value. A positive difference of abundance indicates an enhanced abundance of formulas in the fresh sample compared to the aged sample. Similarly, a negative difference of abundance indicates an enhanced abundance of formulas in the aged sample compared to the fresh sample. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S6: Kendrick mass defect diagrams for each of the Po Valley samples, partitioned by elemental group (rows) and sample (columns) as indicated in the Figure. The molecular formulas unique to each sample are color scaled to the number of oxygen atoms in the assigned formula; grey points represent formulas which are common. Homologous series of molecular formulas are visible as horizontal rows of points, where formulas which are unique to a sample may make up all or only part of an individual homologous series. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Figure S7: Kendrick mass defect diagrams for each of the Po Valley samples, partitioned by elemental group (rows) and sample (columns) as indicated in the Figure. Molecular formulas are color scaled to the number of oxygen atoms in the assigned formula. The sample names Fresh Fog, Aged Fog, Fresh Aerosol, and Aged Aerosol correspond to SPC0106F, SPC0201F, BO0204N, and BO0213D, respectively.

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Table S1: Summary of the literature structural insights associated with the identified molecular formulas observed in this study. Because the identified molecular formulas may represent a variety of structural isomers, we note that matched molecular formulas do not necessarily correspond to the same molecular structure or atmospheric origin. The normalized abundances are indicated for each sample, where “ND” (not detected), “Low” (≤ 3%), “Med”, (> 3% and ≤ 15%), “High” (> 15% and ≤ 50%) and “Very High” (> 50%). Molecular formulas from the literature are provided with their references.

Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C4H6O5 ND ND ND Low syringol aqSOA A

C5H6O3 ND ND ND Low ambient cloud water B

C5H6O4 ND Low ND Low syringol aqSOA A, B

C5H6O5 ND ND ND Low syringol aqSOA A, C-E (ketoglutaric acid)

C5H8O4 ND Med ND Low ambient cloud water B-F (methylsuccinic acid and glutatric acid)

C5H8O5 ND ND ND Low ambient cloud water B, G (hydroxyglutaric acid)

C6H4N2O5 High Med Low Low dinitrophenol H

C6H5NO3 High High Med Med nitrophenol B, H

C6H5NO4 High High Very High Med nitrocatechol B, H

C6H5NO5 ND ND Med Low ambient cloud water B

C6H6O3 ND ND ND Low C-E

C6H6O4 ND Low ND Med phenol SOA

C6H6O5 ND ND ND Low syringol aqSOA A

C6H8O4 Low Med ND Med ambient cloud water B

C6H8O6 ND ND ND Low syringol aqSOA A

C6H10O3 ND Low ND Low ambient cloud water B

C6H10O4 ND Med ND Low ambient cloud water B-F (methylglutaric acid and adipic acid)

C6H10O5 ND Low ND Low levoglucosan B-F, I

C6H10O6 ND ND ND Low dimethyltartaric acid J

C7H5NO5 High Med Med Med nitrosalicylic acid H

C7H6O2 Med Med ND Low ambient cloud water B, F (benzoic acid)

C7H6O3 Med Med Med Med phenol aqSOA A, C-E (dihydroxybenzaldehyde and hydroxybenzoic acid)

C7H6O4 Med Low Low Med phenol aqSOA A

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C7H6O5 ND Low ND Low syringol aqSOA K

C7H6N2O5 Med Med Med Low ambient cloud water B, L

C7H6N2O6 Med ND Med Low ambient cloud water B, L

C7H7NO3 High High Med High methyl-nitrophenol B, H

C7H7NO4 High Med Med Med ambient cloud water B,H (nitroguaiacol and methyl-nitrocatechol)

C7H7NO5 Med Low Med Med ambient cloud water B

C7H8O3 Med Low ND High SOA

C7H8O4 Med Med Low Low guaiacol SOA

C7H8O5 Low Med Low Med guaiacol SOA

C7H8O6 Low Low ND Med guaiacol SOA

C7H10O4 Low Med Low Med ambient cloud water L

C7H10O6 Low Low Low Med guaiacol aqSOA A

C7H12O4 ND Med ND Low ambient cloud water C-E, L (pimelic acid)

C7H12O5 ND Low Low Med biogenic SOA (hydroxy- G dimethylglutaric acid)

C7H12O6S ND Low ND Low ambient cloud water L

C7H12O7 Low ND ND ND syringol aqSOA A

C7H14O5S Low Med ND Low dodecane aqSOA L

C7H14O6S ND Low ND Low ambient cloud water L

C8H5NO4 Med Low Med Low ambient cloud water B

C8H6O3 Med Med Low Low ambient cloud water and A, B guaiacol aqSOA

C8H6O4 Med Very High Low Low ambient cloud water B-F (phthalic acid)

C8H6O5 Med Med ND Low phenol aqSOA A

C8H7NO3 Med ND Med High ambient cloud water B

C8H7NO4 Med Med Med High ambient cloud water B

C8H7NO5 High Med Med High ambient cloud water B

C8H8O2 Med Med Low Low ambient cloud water (o- B, F toluic acid)

C8H8O3 High Med Med Low ambient cloud water B-E (vanillin)

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C8H8O4 Med Med Low Low vanillic acid C-F, I

C8H9NO3 Med Med Med Low ambient cloud water B

C8H9NO4 High Med Very High High ambient cloud water B

C8H9NO5 High Med High High ambient cloud water B

C8H10O3 Med Low ND Low syringol A,F, I, K

C8H10O4 Low Med ND Low syringol SOA

C8H10O5 Med Med Low Med syringol aqSOA K-L

C8H10O6 Low Med Low Med syringol aqSOA A

C8H10O7 ND Low ND Low syringol aqSOA A

C8H12O6 Med Med Low Med biogenic SOA (methyl- G butanetricarboxylic acid)

C8H12O7S ND Low ND ND ambient cloud water L

C8H12O8S Med Low ND Low ambient cloud water L

C8H14O6S Low Med ND Low ambient cloud water L

C8H14O7 Med ND ND ND methylglyceric acid J dimer

C8H14O7S ND Low ND ND ambient cloud water L

C8H16O6S Med Med Low Med ambient cloud water M

C9H7NO4 Med Low Med Low ambient cloud water B

C9H8O2 Med Low Low ND ambient cloud water B

C9H8O3 Med Med Med Med ambient cloud water B-E (coumaryc acid)

C9H8N2O6 Low ND Low Med ambient cloud water L

C9H9NO3 Med ND Low Med ambient cloud water B

C9H9NO3 Med ND Low Med laboratory brown carbon N aqSOA

C9H9NO4 Med Low Med Med ambient cloud water B

C9H10O3 Med Low Low Low laboratory brown carbon A, C-F, K, O aqSOA (acetovanillone and dimethoxybenzaldehyde)

C9H10O4 Med Med Low Low syringol aqSOA C-F, I, K ()

C9H10O5 Med Med Low Low C-F, I

C9H11NO3 Med Low Low Med tyrosine

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C9H11NO4 Med Low Med Med ambient cloud water B

C9H12O3 Low Low ND Low methylsyringol F

C9H12O5 Med Med Low Low ambient cloud water L

C9H12O7S Low ND ND ND ambient cloud water L

C9H12N2O3 ND ND ND Low laboratory brown carbon O aqSOA

C9H12N2O3 ND ND ND Low laboratory brown carbon N aqSOA

C9H13NO5 Low ND ND Med laboratory brown carbon N aqSOA

C9H14O3 Low Low ND Low ketolimononaldehyde P

C9H14O4 Med Med ND Low biogenic SOA (pinic G acid)

C9H14O6S Med ND ND ND ambient cloud water L

C9H14O7S Low Med ND Low ambient cloud water L

C9H14O8S Med Med ND Low ambient cloud water L

C9H14O9S Low Low ND ND ambient cloud water L

C9H15NO8S Very High Very High Low Very High ambient cloud water L

C9H16O4 High Med Low Low azelaic acid C-F

C9H16O6S Med Med ND Med ambient cloud water L

C9H16O7S Low Med ND Low ambient cloud water L

C9H16O8S ND Low ND ND ambient cloud water L

C9H18O6S Med Med Low Med ambient cloud water, I, M marine SOA

C9H18O8S ND ND ND Low ambient cloud water M

C10H8O3 Med Low Med Low syringol aqSOA A

C10H10O4 High Med Med ND ferrulic acid C-E

C10H12O2 Low Low ND Low eugenol F

C10H12O4 Med Low Low Low C-E

C10H14O3 Low Low ND Low ketopinic acid G

C10H14O5 Med Med Low Low ambient cloud water L

C10H14O6 Med Med ND Low ambient cloud water L

C10H14O7S Med ND ND ND ambient cloud water L

C10H14O8S Low Low ND ND ambient cloud water L

C10H16O3 Low Low ND Low pinonic acid C-E, G

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C10H16O6S Med ND ND ND ambient cloud water L

C10H16O7S Med High ND Low ambient cloud water L

C10H16O8S ND Med ND Low ambient cloud water L

C10H16O9S Low Low ND ND ambient cloud water L

C10H17NO7S Very High Very High High Very High ambient cloud water L

C10H17NO10S Med Med Low Med ambient cloud water L

C10H18O5S ND Med ND ND ambient cloud water L

C10H18O7S Med Med ND Low ambient cloud water L

C10H18O8S Low Med ND ND ambient cloud water L

C10H19NO9S High Med Low Med ambient cloud water M

C10H20O5S Med Med Low High ambient cloud water M

C10H20O6S Med Med ND Med marine SOA I

C10H20O7S Low Low ND Low ambient cloud water L

C11H10O8 ND Low ND ND phenol aqSOA A

C11H21NO9S Med Med Low Med ambient cloud water M

C11H22O5S Med Med Low High ambient cloud water M

C11H22O6S Med Med ND Med marine SOA I

C12H10O2 Low ND Low ND phenol aqSOA A, K

C12H10O3 Low ND Low Low phenol aqSOA A

C12H10O4 ND ND Low Low phenol aqSOA A

C12H10O7 Med Med Low Low syringol aqSOA K

C12H10N2O8 ND ND Low ND ambient cloud water B

C12H11NO4 Med ND Low Low laboratory brown carbon N aqSOA

C12H12O6 Med Med Low Low syringol aqSOA K, L

C12H12O7 Med Med Low Low syringol aqSOA A, K, L

C12H14O4 Med Low Low Med syringol aqSOA A

C12H14N2O4 ND ND ND Low laboratory brown carbon O aqSOA

C12H14N2O4 ND ND ND Low laboratory brown carbon N aqSOA

C12H16N2O5 ND ND ND Low laboratory brown carbon O aqSOA

C12H17NO7 Low Low Low Low laboratory brown carbon N aqSOA

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C12H20O7S Med Med ND Med ambient cloud water L

C12H22O7S Med Med Low Med ambient cloud water M

C12H23NO9S Med Med Low Med ambient cloud water M

C12H24O5S Med Low Low High ambient cloud water M

C12H24O6S Med Med ND Med marine SOA I

C12H26O4S High ND Med Low ambient cloud water M

C13H10O3 ND ND ND Low guaiacol aqSOA A

C13H10O4 Med Low Low ND guaiacol aqSOA A

C13H10O5 Med ND Low Low guaiacol aqSOA A

C13H12O4 ND ND Low Low guaiacol aqSOA A

C13H12O6 Med Med Low Low guaiacol aqSOA A, L

C13H14O5 Med Med Med Med syringol aqSOA A

C13H14O7 Med Med Low Low syringol aqSOA A

C13H16O8 Med ND Low ND syringol aqSOA A

C13H24O7S Med Med Low Med ambient cloud water M

C13H26O6S Med Low Low Med ambient cloud water, I, M marine SOA C14H10O5 Med Low Low Low phenol aqSOA A

C14H12O6 Med Low Low Low guaiacol aqSOA A, L

C14H12O7 Med Med ND Low syringol aqSOA A

C14H14O4 ND ND Med Low guaiacol aqSOA A, I, K

C14H14O5 Med Low Low Med guaiacol aqSOA A, K, L

C14H14O6 Med Med Low Med syringol aqSOA and A, K guaiacol aqSOA

C14H14O8 Med Med ND Low Syringol aqSOA A

C14H16O8 Med Med Low Low syringol aqSOA A

C14H16O9 Med Low ND Low syringol aqSOA A

C14H16O10 Low Low ND Low syringol aqSOA A

C14H20O9 Low Low ND Med ambient cloud water L

C14H24O8 ND Low ND ND ambient cloud water L

C14H27NO9S Med Low Low Med ambient cloud water M

C14H28O5S Med Low Low Med ambient cloud water M

C14H28O6S Med Low Low Med ambient cloud water M

C14H30O4S Med ND Low Med ambient cloud water M

C15H14O6 Med Low Low Low syringol aqSOA K, L

C15H14O8 Med Med Low Low syringol aqSOA K

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Formula SPC0106F SPC0201F BO0204N BO0213D Possible Identity Reference*

C15H16O6 Med Med Low Low syringol aqSOA A, K, L

C15H16O8 Med Med ND Low syringol aqSOA A

C15H16O9 Med Med ND Low syringol aqSOA A, K, L

C15H18O7 Med Med Low Low syringol aqSOA A, K, L

C15H18O9 Med Med Low Low syringol aqSOA A

C15H18O10 Low Low ND Low syringol aqSOA A

C15H24O9 Low Low ND Low ambient cloud water L

C15H29NO9S Med Low Low Med ambient cloud water M

C15H30O6S Med Low Low Med ambient cloud water M

C16H18O6 Med Low Low ND syringol aqSOA A, I, K, L

C16H18O7 Med Med Low Low syringol aqSOA A

C16H18O9 Med Med ND Low syringol aqSOA K

C16H24O11S ND Low ND ND ambient cloud water L

C16H31NO9S Med Low Low Med ambient cloud water M

C17H33NO9S Med Low Low Med ambient cloud water M

C18H12O5 Low ND ND Low phenol aqSOA A

C18H14O4 Low ND Low Low phenol aqSOA A

C18H26O12S ND Low ND ND ambient cloud water L

C18H28O11S Low Low ND ND ambient cloud water L

C18H38O6S Low ND ND Low ambient cloud water M

C19H30O12S Low ND ND ND ambient cloud water L

C20H14O6 Low ND Low ND phenol aqSOA A

C20H16O7 Med ND Low Low guaiacol aqSOA A

C20H18O6 Med ND Low Low guaiacol aqSOA A

C20H26O3 Low ND Low ND oxodehydroabietic acid F

C20H28O2 ND ND Low ND dehydroabietic acid F

C21H18O8 Med Low Low Low guaiacol aqSOA A

C21H20O6 Low ND Low Low guaiacol aqSOA A, K

C21H20O8 Med ND Low ND guaiacol aqSOA A

C28H26O8 ND ND Low Low guaiacol aqSOA A *References: (A) Yu et al. (2016); (B) Desyaterik et al. (2013); (C) Pietrogrande et al. (2014a); (D) Pietrogrande et al. (2014b); (E) Pietrogrande et al. (2015); (F) Mazzoleni et al. (2007); (G) He et al. (2014); (H) Kitanovski et al. (2012); (I) Dzepina et al. (2015); (J) Herrmann et al. (2015); (K) Yu et al. (2014); (L) Cook et al. (2017); (M) Zhao et al. (2013); (N) Hawkins et al. (2018); (O) Lin et al. (2015) and (P) Nguyen et al. (2013).

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